The communications industry is a rapidly growing industry that affects almost every other major industry. Because of the field's rapid growth, the management of communication systems, including routing traffic within the systems, has become more difficult as the systems have become increasingly larger and more complex. Many modern communication systems, therefore, include the ability to provide label-switched routing in order to forward IP packets based on Layer 2 information, as opposed to conventional Layer 3-based routing.
Label-switched routing provides numerous advantages which include higher performance and lower cost due to simplified forwarding, separation of typically complex flow classification from forwarding which results in the ability to process increasingly complex flow classification, and low-overhead source routing. Label-switched routing also facilitates traffic engineering by mapping label-switched paths to traffic-engineered routes and facilitates Quality of Service (QoS) by mapping label-switched paths to different per-hop behaviors.
Conventional wireless networks provide label edge routing functionality at the edge through a packet data serving node. The serving node stores information for the wireless device when a session for the wireless device is created. The serving node then performs a label exchange with an adjacent network node in order to establish a label-switched path for forwarding the session's traffic to and from the network.
Thus, in a conventional wireless network, when the serving node receives a packet from a wireless device, the serving node examines the Layer 3 contents of the packet and performs a look-up of the stored information for that wireless device. The serving node then classifies the flow, determines the type of processing to apply to the packet, and obtains labels to insert into the packet based on the results of looking up the stored information. Similarly, when the serving node receives network traffic destined for the wireless device via the label-switched path, the serving node is responsible for removing the label, reconstructing the packet and forwarding the packet to the wireless device.
Therefore, in providing label-switched routing in this manner, the resources of the serving node are heavily utilized for every packet that is received at the serving node. In addition, the granularity of flow classification is limited by the amount of information that may be stored in the serving node for the wireless devices in the network. Generally, this stored information relates only to an aggregation of traffic to and from the wireless devices but does not include any information about the number or types of flows that may be terminated beyond the wireless device.